Let me say from the outset that disorientating someone with a bright light to their eyes is not my ideal self defense option. However, if you live in a city like mine, you can wind up getting hauled in along with the perp if you are found to have any of a host "weapons". Carry permits are extremely difficult to obtain, forget about a knife of any size or orientation, a collapsible baton will get you a host of legal woes.
Obviously avoiding trouble is the best option, but if you wanted to momentarily disorient someone with a bright light what would be your recommendation.
Thanks in advance for any suggestions.